Amino acids assimilation

Oshita, K., Kubota, M., Uchida, M., Ono, M. (1995) Clarification of the relationship between fusel alcohol formation and amino acid assimilation by brewing yeast using C-labelled amino... 

Experimental Separation of Stages in Amino Acid Assimilation. 356... 

In the introduction the idea was put forward that antibiotics could be used as tools to assist in the elucidation of anabolic reactions. As each stage in amino acid assimilation has been uncovered in the course of these studies, the action of a number of antibiotics has been tested on that stage. The antibiotics used have been tyrocidin, penicillin, aureomycin, chloramphenicol (chloromycetin), terramycin, neomycin, streptomycin, bacitracin, and polymjrxin. With the exceptions of streptomycin and polymyxin, significant inhibitions of some stage or other in amino acid assimilation have been observed for all these antibiotics. These points of interference are summarized in Table XVI. 

Effect of Antibiotics and Inhibitors on SUj es of Amino Acid Assimilation in Staphylococcus aureus Duncan... 

Figure 10.4. Effect on apatite-collagen isotopic fractionation due to inhibition of amino acid production and preferred use of exogenous amino acids. Carnivore and herbivore, both based on C3 plants, have similar bulk isotopic composition of total edible tissues (T), leading to similar 5 C for apatite carbonate (AP). Collagen (CO) of carnivore is more enriched in Cthan that of herbivore, because of preferential utilization of amino acids derived from protein (P) of herbivore flesh in construction of carnivore s proteins. C ss = assimilated carbon.

Most plant species are able to absorb and assimilate nitrate, ammonium, urea, and amino acids as nitrogen sources, but the response to a particular form of nitrogen varies from species to species (114). For example, optimal growth of tomato roots occurs in soil with a ratio of nitrate to ammonium of 3 1 and is inhibited if the ammonium concentration is too high (115). By contrast, white spruce has a strong preference for ammonium (116), whereas some arctic sedges prefer amino acids (117). 

Figure 11 The different steps of nitrogen metabolism in the extraradical hyphae, ccto-mycorrhizal roots, and roots of the host plant. I, absorption 2, assimilation 3. storage 4. translocation A, extramatrical hyphae B. ectomycorrhizal sheath C, Hartig net D, root cortical cells AA amino. acids.

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